Typically, tool holder mechanisms utilize a conical bore whose axis is offset from the threaded section of the locking pin receiving hole to tilt the locking pin into abutment with the cutting insert. These designs are difficult to machine because the location of the conical bore must be maintained within a relatively tight tolerance if it is to achieve the desired tilting of the locking pin. Therefore, there is a need to provide a tool holder for clamping an insert that is simple to manufacture and has improved manufacturing tolerances while requiring fewer components.